Extensible seat for chairs



April 22, 1952 GRElTZER 2,593,750

EXTENSIBLE SEAT FOR CHAIRS Filed May 20. 194? 2 SHEETSSHEET 1 I l l I 20X6 wvs/vrox 7 /i/y/e 698157721676 A ril 22, 1952 M. GREITZER EXTENSIBLESEAT FOR CHAIRS Filed May 20, 1947 2 SHEETS--SHEET 2 LE. :55: Q.

J5 E-JG Patented Apr. 22, 1952 UNITED S TATE S PATE NT O FFICEEXTENSI-BLE SEAT FOR CHAIRS- Meyer Greitzer, Los Angeles, Calif.

Application May'20, 1947, Serial No. 749,150

2 Claims.

My invention relates generally to chairs and. more particularly to theseats thereof, the principal object of my invention being to provide asimple, practical and efficient unitary structure carrying the chairseat and adapted to be mounted on the chair frame, and which structurefolds or collapses vertically, so as to elevate the seat and therebytemporarily convert an ordinary chair into a high chair for childrensuse.

Further objects of my invention are, to provide a chair seat elevatingstructure having simple and effective means for automatically andpositively locking the folding structure when elevated, thus entirelyeliminating the possibility of collapse of the structure while elevatedand further, to provide a seat elevating structure 'of the characterreferred to that is simple, strong, durable, light in weight and whichis capable of being easily and quickly applied to the chair frame andits seat.

With the foregoing and other objects in View, my invention consists incertain novel features of construction and arrangement of parts whichwill be hereinafter more fully described and claimed and illustrated inthe accompanying drawings, in which:

Fig. 1 is a top plan view of the collapsible seat elevating structure.

Fig. 2 is a front elevational view of the structure applied to a chairframe and its seat with the latter in its normal or lowered position.

Fig. 3 is a front elevational view with the seat in elevated position.

Fig. 4 is a vertical section taken on the line 4-4 of Fig. 1 and showingthe seat in elevated position.

Fig. 5 is a cross section taken on the line 5-5 of Fig. 3.

Fig. 6 is a detail section taken on the line Ii6 of Fig. 5.

Referring by numerals to the accompanying drawings which illustrate apreferred embodiment of my invention, I0l 0 designates the horizontalseat supporting rails of a tubular metal chair frame, which railsprovide a support for my seat elevating structure, the latter includinga substantially rectangular base frame II, preferably composed from asingle piece of channel iron with its flanges outwardly presented.

Rails I0 fit snugly between the flanges of the side rails of frame II,with pins I2 projecting from the webs of the side rails throughapertures formed in the inner portions of rails ID, as seen in Figs. 2,3 and 4.

This means for securing the chair seat carry- 2 ing frame is set forthin U. S. Letters Patent No. 2,390,878, issued tome December 11, 1945.

A conventional chair seat S is secured on top of a pair of parallelrails I3, preferably angle bars, by screws I4.

Arranged between the end portions of rails l3 and the front and rearrails of frame II, are upper and lower hinge plates 15 and I6respectively. The ends of the upper plates I6 are bent at right anglesto form flanges ll, the upper ends of which are pivoted to pins orrivets I8 adjacent the ends of rails I3, and the lower ends of flangesIS on lower plate I6, are pivoted to pins or rivets 20 on the front andrear railsof base frame I I.

The lower ends of flanges I 5 and upper ends of flanges I'Q'arepivotally connected by means of pins 21 same being offset outwardly fromthe vertical planes occupied by pivots I8 and 20, thus forming hingejoints which prevent accidental collapse of the folding structure.

Located on the outer faces of plates I5 and I6 adjacent their ends areretractile springs 22, the upper ends of which are anchored to loops 23struck from plates I 5 and the lower ends of these springs engage hooks24, struck from plates .IB short distances from the joint between saidplates I5 and from the hinge pins 2 I.

When the folding structure is open and elevated, springs 22 are undertension, thus yieldingly maintaining the plates I5 and I6 againstfolding movement and collapse, and when the hinged ends of said platesare pushed inwardly, said springs act to instantly fold or close thecollapsible structure.

To secure the folding structure in open position and lock same againstcollapse, a plate 25 is connected by hinges to the front rail of faceframe I0, and projecting from the hinged edge of said plate is a shorthandle 21.

When the structure is open with plates l5 and I6 vertically disposed,plate 25 occupies position between said plates I5 and I6, as seen inFig. 5, thus effectively preventing the latter from folding inward.

The lower ends of retractile springs 28 are connected to frame I0 abovehinges 25, and the upper ends of said springs are connected to plate 25near its free edge. 7

A stop 29 on plate I5 near one end, limits the upward swinging movementof the locking plate 26. When collapsed, the folding structure isdisposed within base frame ID, as seen in Figs. 1 and 2, and thus seat Sis supported in its normal position just above side rails III of thechair frame.

To elevate the seat for children's use, said seat is lifted and whenhinge plates 15 and I6 are vertically disposed with hinge pins 2|occupying vertical planes outwardly from that occupied by pivots l8 and20 locking plate 25 will, under the influence of springs 28, be swungupward against stop 29 thus, in effect locking the folding structureagainst accidental collapse.

To lower the seat, plate 26, by means of handle 27 is swung downward toa horizontal position below frame l0, and the hinged edges of plates Iand I 6 are now pressed inward or toward each other so that rails I3 andseat S carried thereby will, under tension strains of the springs 22,move to their normal lowered position. 1

An especially desirable feature of my invention is the structureincluding the hinge plates l5 and I6 and plate 25, which by a singlemovement or action, shifts the seat S into a self locked elevatedposition, and when the locking means is released, theseat by a singleaction, moves to its normal position on the base frame.

Thus it will be seen that I have provided a collapsible seat support forchairs, which is simple in structure, inexpensive of manufacture andvery effective in performing the functions for which it is intended.

Minor changes in the size, form and construction of the various parts ofmy improved collapsible chair seat may be made and substituted for thoseherein shown and described without departing from the spirit of theinvention,-the scope of which is set forth in the appended claims.

seat, of pairs of hinged plates connecting said frame and seatretractile springs disposed beof the hinge connection tween the membersof each pair of hinged plates, a plate hinged to one side of said framebetween said pairs of hinged plates and retractile springs associatedwith said hinged plate and frame for swinging said plate into positionbetween said pairs of hinged plates when the latter are swung intovertical positions to elevate said seat.

2. The combination with a chair including side rails, of a frame mountedon said side rails,

a "chair seat, plates having theirv lower ends pivotally connected tothe frame near its sides, hinge plates pivotally connected to said seatnear its sides, the lower ends of said last mentionedhinge plates beinghinged to the upper ends of the first mentioned hinge plates andretractible springs having their ends secured to said hinge platesandextending across the axis between said plates.

MEYER GREITZER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED sTATEs PATENTS

